Stock-level indicator



March 13, 1928. 1,662,484

P. D. WRXGHT' STOCK LEVEL INDICATOR Filed Oct. '7, 1937 2 Sheets-Sheet 1 2404 D. WE/QHT,

March 13, 1928.

P. D. WRIGHT STOCK LEVEL INDICATOR Filed Oct. '7, 1927 2 Sheets-Sheet 2 le'gff.

lnvvuior: P404 5. WE/GHZ I /J #r/ieg Patented Mar. 13, 1928.

UNITED STATES PAUL D. WRIGHT, OF EDGEWOOD BOROUGH, PENNSYLVANIA.

STOCK-LEVEL INDICATOR.

Application filed October 7, 1927. Serial N0. 224,643.

This invention relates to stock level indicaters for blast furnaces, and has for its object the provision of a novel form of apparatus which will not be injured when the furnace has a top explosion or slip.

Indicators of this general class have here tofore been operated directly'or indirectly by the furnace charging bell operating mechanism and have used a stiff or rigid try-rod movably mounted within the furnace.

The present apparatus has improved operating mechanism which is separate from the operating mechanism of the charging bell, and also is provided with a flexible try-rod or measuring member which serves as a flexible link in the system which will not be in jured when the furnace makes a top explosion or slip.

In the drawings- Figure -1 is a vertical sectional elevation through a furnace having my invention mounted thereon.

Figure 2 is an enlarged fragmentary sectional detail view showing the manner in which the try-rod or cable is passed into the furnace.

Figure 3 is an enlarged elevation of the operating and indicating mechanism.

Figure 4 is acsectional plan taken on the line IV-IV of Figure 3.

Figure 5 is a fragmentary View showing the mounting for the upper sheave of the power operating unit.

Referring more particularly to the draw ings, the numeral 2 designates the furnace as a whole which has the usual hoppers 3 and 4 and bells 5 and 6 at its top and a top closing plate 7.

The stock in the furnace is indicated at A, and it is desirable to know at all times just what the level of the stock is relative to the normal stock line indicated at B.

In view of the above, I have provided a stock indicator which consists of a wire cable, chain or other flexible element 8 which passes into the furnace 2 through a stuffing box and gland 9 in the top or closing plate 7 of the furnace, and is provided at its furnace end with aweight' member 10. The cable 8 is trained over a sheave 12 above the furnace 2 and then down and over a sheave 14 and has its end secured to an indicator block 15 slidably mounted on guide-rods 16.

The block 15 is rovided at diametrically opposite points with wedge-shaped or tapered projections 17, 17. The projection 17 is adapted to cooperate with a gage-plate 18 to indicate the level of stock in the fur nace.

A power means for reciprocating the block 15 is mounted along the side of the guiderods opposite from the gage-plate 18 and comprises a base 20, a motor 21 mounted on said base and having a worm 22 secured on its armature shaft, which worm is in mesh with a worm-wheel 23 on a shaft 24 journaled in bearings 25 on the base 20.

The shaft 24 has a sprocket 26 keyed thereon which is connected to a sprocket 27 by a than 28. The sprocket 27 is positioned directly above the sprocket 26 and is mounted on a shaft 29 journaled in bearings 30 on an overheadsupporting structure 31.

The sprockets 26 and 27 are so positioned relative to the block 15 that the stretch of the chain 28 next to said block 15 will extend into the path of the projection 17 so that the links of the chain 28 will engage said projection and ride over its tapered or inclined faces. 1

The chain 28 is provided with a dog 32 which projects outwardly therefrom and is adapted to engage the projection 17 on the block 15 when the chain 28 is moved around the sprockets 26 and 27, and to move the block 15 downwardly along the guide-rods 16 until the dog reaches the lower sprocket 26, at which point the dog will automatically disengage from the projection 17 as it moves around the sprocket 26.

When the block 15 is moved downwardly along the guide-rods 16 by the dog 32 the fiexihleelement'8 and weight 10 will be pulled upwardly in the furnace and when the dog 32 is disengaged from the projection 17 the block 15, element 8 and weight 10 will be free to return to their normal position with the weight resting on the stock in the furnace. The return movement of the weight 10, element 8 and block 15, however, is retarded by the braking action of the lug 17 on the block 15 as it moves along the chain 28 so as to prevent a sudden drop of the weight into the furnace which would cause the weight to sink into the stock.

The motor 21 is adapted to be automatically controlled by means of a standard automatic control mechanism (not shown) operable by the furnace bell operating mechanism, and said control mechanism will preferably be arranged to operate the motor 21 when the furnace bell is opened so as to cause the block 15 to move downwardl and raise the weight 10. When the block approaches the lower limit of its travel and prior to the disengagement of the dog 32 from the projection 17, the motor will be automatically stopped. \Vhen the furnace bell is closed the motor 21 will again be operated to move the chain 28 and dog 82 around the sprocket 26, thus releasing the block 15 and permitting the block 15 to travel upwardly along the guide-rods 10 and the weight 10 to lower onto the stock in the furnace. The projection 17 on the bloclceiigaging the links of the chain 28 will prevent the weight from moving rapidly in its descent into the furnace. The motor 21 will continue to operate until the lug or dog 32 has passed over the upper sprocket 27 into position to again engage the projection 17 on the block 15 when it will automatically stop in readiness to again engage and pull down the block 15, when the furnace bell is opened or raised to receive another charge of stock.

The position of the projection 17 on the block 15 relative to the gage marks on the gage-plate 18 when the weight 10 is resting on the stock in the furnace, indicates the amount of stock in the furnace to the operator. It will be understood, however, that any suitable recording apparatus may be connected to the block 15 or its associated mechanism to record the stock level, if desired.

If the motor control mechanism connected with or operated by the furnace bell should, for any reason, become inoperative, the motor operating the stock indicating mechanism would not become broken or jammed due to the fact that the dog 32 would simply disengage from the lug 17 on the block 15 at each cycle of movement, and thereby cause a constant up and down movement of the indicating mechanism.

In case of a top explosion or slip in the furnace the indicating mechanism will not be damaged, due to the flexible element 8 which will yield to the forces of the explosion and return to normal position.

While I have shown and described one specific embodiment of my invention it will be understood that I do not wish to be limited thereto since various modifications may be made without departing from the scepe of my invention as defined in the appended claims.

I claim- 1. The combination with a furnace, of a stock level indicator comprising, a weight within the furnace, an indicator block, a flexible connection between the block and weight, electrically operated means for reciprocating the block to cause the weight to alternately raise above and descend onto the stock in the furnace, and a gage-plate cooperating with the block to indicate the stock level within the furnace.

2. The combination with a furnace, of a stock level indicator comprising, a weight within the furnace, an indicator block, a flexible connection between the block and weight, guide-rods on which the block is mounted for vertical reciprocatory movement, a pair of said guide-lods, a chain trained over the sprockets, a motor connected to and adapted to rotate one of said 5 )rockets, and means carried by said chain adapted to engage with and pull the block dowir wardly along the guide-rods so as to raise the weight within the furnace, and to automatically release the block at a predetermined point and thereby permit the weight to descend in the furnace and to elevate the block on said guide-rods.

3. The combination with a furnace, of a stock level indicator comprising, a weight within the furnace, an indicator block, a flexible connection between the block and weight, guide-rods on which the block is mounted for vertical reciprocatory movement, an indicator plate at one side of the guide-rods, a pair of vertically spaced sprockets mounted at the other side of the guide-rods, a chain trained over the sprockets, a pair of diametrically opposite projections on the block, one of said projections overlying said gage-plate and the other projection extending into the path of said chain, a motor adapted to rotate one of the Sprockets, a dog connected to the chain and adapted to engage the projection on said block extending into the path of travel of said chain, said dog being arranged to engage said projection when the chain is moved around the sprockets and to force the block downwardly along the guide-rods to raise said weight in the furnace, and to be automatically released from said projection when the portion of the chain to which the dog is secured moves around the lower of the sprockets so as to permit the weight to move downwardly in the furnace and cause the block to move upwardly on the guiderods, the said projection extending into the path of the chain being adapted to retard upward movement of the block and downward movement of the weight in the furnaee.

In testimony whereof, I have hereunto set my hand.

PAUL D. WRIGHT.

lltl 

